Explaining the Evolution of Passenger Vehicle Miles Traveled in the United States
After growing steadily for several decades, passenger vehicle miles traveled (VMT) in the United States unexpectedly leveled off in the 2000s. The underlying causes have major implications for future US oil consumption and greenhouse gas (GHG) emissions; but despite speculation in the popular media, the causes are unknown.
After growing steadily for several decades, passenger vehicle miles traveled (VMT) in the United States unexpectedly leveled off in the 2000s. The growth rate of VMT has since rebounded, and determining the factors that explain these developments has implications for future US oil consumption and greenhouse gas emissions. We show that changes in the demographic and economic characteristics of households in the United States, rather than changes in driving habits, explain most of the recent dynamics. These results suggest that over the next decade, VMT in the United States will continue to grow roughly at historical rates, causing substantially higher oil consumption and greenhouse gas emissions than if persistent changes in household driving habits explained the recent changes in VMT.
Key findings
- Changes in demographics and economic characteristics of households in the United States, rather than changes in driving habits, explain the growth in passenger vehicle miles traveled.
- Over the next decade, miles traveled will increase nearly at historical rates, causing substantially higher oil consumption and GHG emissions than if persistent changes in household driving habits explained the recent changes in VMT.
- Our predicted growth rate implies that future oil consumption and GHG emissions will be about 10 percent higher than if VMT were to remain at 2015 levels, increasing the challenge of meeting the US international pledge to reduce GHGs.
Authors
Clayton Munnings
